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Related papers: spinney: A Form Library for Helicity Spinors

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We present an alternative approach for calculating helicity amplitudes for processes involving both massless and massive fermions. With this method one can easily obtain covariant expressions for the helicity amplitudes. The final…

High Energy Physics - Phenomenology · Physics 2014-11-17 R. Vega , J. Wudka

Precision calculations in hadronic processes at high energy colliders are crucial for improving the understanding of the standard phenomena as well as for the discovery of new physics. Spinor-helicity formalism serves as one of the most…

High Energy Physics - Phenomenology · Physics 2025-11-10 Vibhu Pandya , Radhika Vinze , Anuradha Misra

We establish a simple formula for the minimal dimension of operators leading to any helicity amplitude. It eases the systematic enumeration of independent operators from the construction of massless non-factorizable on-shell amplitudes.…

High Energy Physics - Phenomenology · Physics 2020-05-29 Gauthier Durieux , Camila S. Machado

One of the open challenges in quantum computing simulations of problems of chemical interest is the proper enforcement of spin symmetry. Efficient quantum circuits implementing unitaries generated by spin-adapted operators remain elusive,…

Quantum Physics · Physics 2025-05-07 Ilias Magoulas , Francesco A. Evangelista

We examine recent advancements of the spinor helicity formalism of massive particles. Technical aspects about the formulation of massive helicity spinors are presented in detail to analyze the projective-geometry kinematics of helicity…

High Energy Physics - Theory · Physics 2026-03-03 Camille Gomez-Laberge

We present the Mathematica package SpinorHelicity4D, a dedicated suite for analytic and numeric calculations involving four-dimensional massless and massive spinor-helicity formalism. Analytic features of the package include for example:…

High Energy Physics - Theory · Physics 2023-04-05 Manuel Accettulli Huber

The simplification and reorganization of complex expressions lies at the core of scientific progress, particularly in theoretical high-energy physics. This work explores the application of machine learning to a particular facet of this…

High Energy Physics - Theory · Physics 2025-02-05 Clifford Cheung , Aurélien Dersy , Matthew D. Schwartz

The spinor helicity formalism (SHF) has been efficiently applied to compute perturbative amplitudes in plenty of processes and reactions in gauge theories (including gravity), mostly in the massless case. Some work has been done in order to…

High Energy Physics - Phenomenology · Physics 2017-11-22 Bryan O. Larios

In a recent letter we suggested a natural generalization of the flat-space spinor-helicity formalism in four dimensions to anti-de Sitter space. In the present paper we give some technical details that were left implicit previously. For…

High Energy Physics - Theory · Physics 2020-07-15 Balakrishnan Nagaraj , Dmitry Ponomarev

We compute amplitudes for the process $g^* g^* \to q \overline q V^*$ (two virtual gluons into a quark, antiquark and a boson) at the tree level using the spinor-helicity formalism. The resulting analytic expressions are much shorter than…

High Energy Physics - Phenomenology · Physics 2024-10-11 Jan Ferdyan , Błażej Ruba

Spinorial tools have recently come back to fashion in loop gravity and spin foams. They provide an elegant tool relating the standard holonomy-flux algebra to the twisted geometry picture of the classical phase space on a fixed graph, and…

General Relativity and Quantum Cosmology · Physics 2012-04-17 Maite Dupuis , Simone Speziale , Johannes Tambornino

In this paper a library for spin--angular integration in LS-coupling for many-electron atoms is presented. The software is an implementation of a methodology based on the second quantization in coupled tensorial form, the angular momentum…

Atomic Physics · Physics 2007-05-23 G. Gaigalas

Recently we introduced the chirality-flow formalism, a method which builds on the spinor-helicity formalism and is inspired by the color-flow idea in QCD. With this formalism, Feynman rules and diagrams are simplified to the extent that it…

High Energy Physics - Phenomenology · Physics 2022-07-06 Andrew Lifson , Malin Sjodahl , Zenny Wettersten

SPINAS is a C++ package created for the implementation and numerical computation of phase-space points of constructive amplitudes in particle physics. This package contains a suite of classes and methods for handling particles, propagators,…

High Energy Physics - Phenomenology · Physics 2024-03-14 Neil Christensen

Matrix elements of Wilson-line dressed operators play a central role in the factorization of soft and collinear modes in gauge theories. When expressed using spinor helicity variables, these so-called form factors admit a classification…

High Energy Physics - Phenomenology · Physics 2024-06-07 Timothy Cohen , Marc Riembau

We develop a spinor helicity formalism for five-dimensional scattering amplitudes of any mass and spin configuration. While five-dimensional spinor helicity variables have been previously studied in the context of N=2,4 supersymmetric…

High Energy Physics - Theory · Physics 2024-05-16 Andrzej Pokraka , Smita Rajan , Lecheng Ren , Anastasia Volovich , W. Wayne Zhao

We take a fresh look at Feynman diagrams in the spinor-helicity formalism. Focusing on tree-level massless QED and QCD, we develop a new and conceptually simple graphical method for their calculation. In this pictorial method, which we dub…

High Energy Physics - Phenomenology · Physics 2020-11-03 Andrew Lifson , Christian Reuschle , Malin Sjodahl

This paper describes algorithms to deal with nested symbolic sums over combinations of harmonic series, binomial coefficients and denominators. In addition it treats Mellin transforms and the inverse Mellin transformation for functions that…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. A. M. Vermaseren

Inspired by the flow description of su(N) colour calculations, we recently showed how to simplify the spinor-helicity formalism (at the algebra level two copies of complexified su(2)) by treating each Weyl spinor as part of a flow line with…

High Energy Physics - Phenomenology · Physics 2021-10-11 Joakim Alnefjord , Andrew Lifson , Christian Reuschle , Malin Sjodahl

Methods of spinor calculus in particle physics are described in this series of four chapters written in french. A special emphasis is made on the well-known helicity-coupling scheme which is the guiding thread of all these methods. Numerous…

High Energy Physics - Phenomenology · Physics 2018-04-10 Christian Carimalo